Dolph mentioned this as a possibility in a recent US4 interview (this one) but I didn't know it was this close from happening: he will fly to Bangkok in a couple of weeks to co-star with Tony Jaa in an action comedy.

In two weeks I'll head to Bangkok to be in a Tony Jaa action-comedy (!). Should be interesting. Looking forward to seeing some of his martial-arts moves.

(from what he said in the interview he could then ask Jaa to be in one of his projects if it all goes well)...

Well the "thaï comedy aspect" is something that scares me a little (thaï humor is really exotic and might not fit Dolph, or will totally fit him, but there will not be any middle) but the idea of pairing him with Jaa and seeing Dolph in a thaï boxing extravaganza is really appealing.

Might it be "The Protector 2" that Jaa has in pre prod since a couple of years ? (here's a scene from the 1st one).

You know, yeah. Suddenly his people called and said, “Does Dolph want to be in a Tony Jaa movie?” This was only two months ago. I had to look him up and he seems like a really talented guy. He has been asked to come to America, I think for The Fast and the Furious and a few other things but he turned everything down. So we thought that yeah, if I go over there and work in his picture which is a Thai action comedy, believe it or not, so that should be a fun experience. If I do his film, then he’ll do a film with me where he co-stars with me. Since he hasn’t been seen over here, if we do that fairly quickly, like after The Expendables 3 or something, then that could be very cool. Me and him together could be watchable.

He’s really the next generation of action.

That’s what I hear. A lot of guys I talk to, like I have this trainer I work with who’s a martial artist, he knew him right away. This other guy in London knew him, this Karate guy, he knew him too. So he’s known, not by the general public, but by people who know about movies.